It is a large but fragile sea star, growing to 40 cm (16 in) across, and easily losing its arms (which afterwards regenerate).

The upper surface is clothed in paxillae, spines shaped like a pillar with a flat top bearing tiny spinules.

[2][3] L. ciliaris occurs on the seabed in the eastern Atlantic Ocean from Norway and the Faroe Islands southwards to Cape Verde and the Azores and in the Mediterranean Sea.

It is found in the neritic zone at depths down to 400 m (1,300 ft), mainly on soft sediments into which it sometimes burrows, but sometimes on rock.

The brittle star Ophiocomina nigra was also consumed, but in lesser quantities because it had more efficient escape strategies.

About 4 days after fertilisation, the zygotes develop into bipinnarial larvae, which form part of the plankton.